(a) Field of the Invention
The invention relates to a waterbed structure, and more particularly, to a waterbed structure, which is capable of appropriately increasing a length of a bed body thereof as desired and preventing protective air protection borders thereof from expanding outward, thereby lengthening usage lifespan of the waterbed.
(b) Description of the Prior Art
Referring to FIG. 1 showing an elevational schematic view of a prior double waterbed, the prior waterbed comprises left and right water-containing bodies 1 and bed housing 2. Each of the water-containing body 1 has an outer layer 11; a water inlet plug 12 at an appropriate position of each outer layer 11 and for filling in water; a plurality of equidistant and parallel transverse pull strip spacers 13 that are loop-like and hollow structures; and a water opening 14 disposed at an appropriate position of each transverse pull strip spacer 13 and for allowing injected water to flow through. In addition, upper and lower edges of the transverse pull strip spacers 13 are molded with inner walls of the outer layers 11 of the water-containing bodies 1 using high-cycle heat. The bed housing 2 has an upper surface thereof provided with a plurality of disassembling openings 21 for installing or taking out the aforesaid unfilled water-containing bodies 1 by folding and compressing the water-containing bodies 1 and via the openings 21. Moreover, the water inlet plugs 12 are exactly located at the openings 21 to facilitate injecting water into the water-containing bodies 1. Around the bed housing 2 are air protection borders 3 in form of a continuous frame body. The air protection borders 3 have an air inlet plug 31 for injecting air, and a central air spacer 33 disposed longitudinally to have an overall structure formed as a shape of a square. That is, the air protection borders 3 are constructed with two accommodating chambers 32 for accommodating the two aforesaid water-containing bodies 1 therein. However, the aforesaid structure has several shortcomings below:    1. According to the prior water bed structure, the bed housing and the air protection borders are a formed integral. Supposed wear of either the bed housing or the air protection borders occur after long-term use, it is obliged to replace both the bed housing and the air protection borders as they are an integral structure. Thus, material costs are increased to lower practicability of the water bed.    2. When the water bed structure is in assembly, the openings of the bed housing and the air inlet plugs of the air protection borders are exposed, such that esthetical values of an overall appearance of the water bed are reduced.    3. After a certain period of usage of the prior water bed structure, the air protection borders are likely to dilate to further shorten usage lifespan of the water bed.
Therefore, the inventor provided an advanced waterbed structure. The inventor's prior waterbed of the invention although indeed improves replacement conveniences of the air protection borders and enhances overall practicability of the waterbed, a few shortcomings are nevertheless discovered when put to application:    1. The air protection borders are oval-shaped designs without any reinforcement. Therefore, the air protection borders are likely to expand outward, and usage lifespan of the waterbed is hence shortened.    2. The waterbed has fixed dimensions, and is incapable of increasing length or area thereof. Thus, practical and utilization values are limited.
Therefore, in view of the aforesaid drawbacks of the prior inventions, it is essential to provide a novel and more practical waterbed structure, which overcomes the aforesaid drawbacks and can be more extensively applied to conform to industrial requirements.